Hitherto, a variety of air bag apparatuses have been suggested as disclosed in, for example, Japanese Patent Laid-Open No. 4-50052 in order to prevent a direct shock which is generated between the side wall of a car body, for example, a door, which is deformed attributable to the impact load and a person who is sitting on a seat if a vehicle encounters a side collision.
In general, an air bag apparatus of the foregoing type has a panel-shape side bracket extending forwards and secured to a seat back frame disposed in an outer portion of a seat back in the widthwise direction of the vehicle. Moreover, an air bag module including an air bag body and an inflator is attached to the side bracket. If a collision of the vehicle takes place, gas generated by the inflator causes the air bag body to be unfolded forwards in front of the seat back so that the passenger is protected.
However, the above-mentioned conventional technology having the structure in which the side bracket, to which the air bag module is attached, is formed into a panel-like shape extending forwards has a risk that the cushioning characteristic of a side pad portion is inhibited because the rear surface of the side pad portion comes in contact with the front end of the side bracket if the side pad portion of the seat back is pressed rearwards by the back of the passenger. As a countermeasure against the above-mentioned problem, it might be considered feasible to shorten the length of the side bracket in the lengthwise direction. However, it leads to a fact that the rigidity of the attached air bag module deteriorates unintentionally.